Vitex trees benefit from heavy winter pruning

Question: In a recent column, you quoted an arborist as saying that crepe myrtles will rebloom the following year whether or not the old seed heads were removed during annual grooming. Would this apply to vitex trees as well? My tree has gotten so tall that I can't easily (or safely) reach the seed heads.

Answer: The vitex tree, also known variously as chasteberry, vitex agnus-castus, Texas or Mexican lilac, monk's pepper and others, has been the subject of extensive research by Texas A&M University, which identified and tested several improved varieties to name a Super Star Plant, marketed as the Texas Lilac Vitex.

These were some of their findings. Because vitex blooms on its current season's growth, in order to promote vigorous shoots and blooms the following spring, it must be cut back in late winter. This, of course, will remove the old seed heads, so to answer your question, for vigorous blooms the seed heads must be removed. This is not to say that there won't be any blooms if you leave the seed heads on.

Because vitex reaches 12 to 15 feet and is inclined to be about twice as wide as it is tall, seed heads cannot be easily reached and removed. The A&M research recommends that for best results the trees be heavily pruned or cut to within a few inches of the ground in winter in order to produce the new wood necessary for strong spring bloom. To promote continued bloom over summer, the seed heads should be deadheaded after every bloom cycle.

To stimulate rapid re-blooming and larger flower spikes, three pounds of a slow-release formulation of lawn fertilizer per 100 square feet should be scattered around each plant after spent blooms have been removed. Make sure the lawn fertilizer does NOT contain an herbicide.

Identifying last

week's mystery plant

One person correctly identified the mystery plant: Pearl Belles Kalanchoe (Kalanchoe porphyrocalyx). It is said to be an easy plant to grow and very showy in bloom, featuring bright purple grape-like bellflowers with trumpeted ends. It blooms heavily during shorter days, preferring bright light, morning sun and is hardy to 50 degrees. The plant is a member of the Kalanchoe family, which includes many familiar gift plants. Email me at the address below if you would like a copy of the photo.

Be cautious about bringing in termites

While winter is an excellent time for adding hardy trees, shrubs and ground covers to the landscape, these also are times to be cautious about creating problems that could bring termites into your home. The LSU AgCenter experts offer these suggestions to reduce the possibility of termite problems:

» Place gutters and slope your landscape beds so water drains away from your house.

» Keep mulch in beds adjacent to the house pulled back about 12 inches from the foundation.

» Do not add fill dirt around the foundation or under porches or steps without contacting your termite company for retreatment.

» Do not disturb the chemical barrier at the base of the slab or around pilings by digging into it during bed preparation.

» Promptly remove all scrap wood and wooden debris from the landscape.

» Although studies on the attractiveness of mulches to termites have not been done, pine straw appears to be the mulch that is least attractive to termites. Pine straw has less cellulose than wood, so there is less food available for termites. Avoid using wood chips to mulch beds adjacent to the house or other structures. Consider using mulches that are not plant-based (such as gravel, rubber, rocks) because these are cellulose-free.

» Use metal edging, decorative bricks or border plants to edge your beds. Avoid landscape timbers, railroad ties or other wooden materials that may serve as food for termites. These products can introduce termites into your landscape when brought it.

» When watering, avoid spraying water against the foundation of your house.

» Do not disturb the chemical barrier at the base of the slab or around pilings by digging into this area during bed preparation. The treated area is 4 inches wide and 6 inches deep. Leave at least 2 inches of space between your house and a deck or other wooden structure outside. Build decks and other structures on concrete pads and treat around the pads and posts. Treat under pads, too, and use pressure-treated wood in outdoor settings.

» Do not allow clinging vines, such as English ivy or creeping fig, to grow on the wall of your house. (Courtesy of Dennis Ring)

For questions, comments or for information on purchasing Ann's books, email ajustice@bellsouth.net.

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Vitex trees benefit from heavy winter pruning

Question: In a recent column, you quoted an arborist as saying that crepe myrtles will rebloom the following year whether or not the old seed heads were removed during annual grooming. Would this

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